Their State, in Yours

Another contract has posted a price. Yours should carry that price as they committed it. A repost copies one path from a source commit into your log. Your rules still have to accept the commit that contains it.

Build a source and post the price. Alice signs, as in the earlier pages.

modal contract create --dir ./price-source
cd price-source
modal checkout
modal set-named-id /parties/alice.id example/alice
modal add-rule --name authorized \
  'always([-signed_by(/parties/alice.id)] false)'

model Contract {
  part flow {
    q0 --> q1
    q1 --> q1: +signed_by(/parties/alice.id)
  }
}

modal commit --all -m "Source"
modal commit --path /facts/price.text --value "10 units" --sign example/alice -m "Price"
modal status

Copy the source contract id. It is the Modality spelling.

The destination is Bob's contract. A repost is a commit, and this witness allows Bob's signature on any later step, including the import.

cd ..
modal contract create --dir ./price-dest
cd price-dest
modal checkout
modal set-named-id /parties/bob.id example/bob
modal add-rule --name authorized 'always([-signed_by(/parties/bob.id)] false)'

model Contract {
  part flow {
    q0 --> q1
    q1 --> q1: +signed_by(/parties/bob.id)
  }
}

Commit the bootstrap.

modal commit --all -m "Dest"
modal repost <source contract id> /facts/missing.text --from-dir ../price-source

Path '/facts/missing.text' not found in source contract <source contract id>

Nothing was staged. The source has /facts/price.text. Repost that path. --from-dir reads a local log. Without it, repost reads the hub saved as origin. A source commit that has not been sequenced is refused when the destination is checking a remote source: the snapshot is of a commit the network has ordered.

modal repost <source contract id> /facts/price.text --from-dir ../price-source
modal commit --all --sign example/bob -m "Take their price"
modal checkout
cat state/reposts/<source contract id>/facts/price.text

The file is 10 units. The commit records the source contract, the source path, and the source commit id beside the value. After it is accepted, the destination path is ordinary state.

The idea

A repost is a copy of one path at one source commit. The value is theirs, from that commit. The method label is +REPOST. A witness that only allows +POST has to allow +REPOST too, or leave the step unlabeled, before the import commits. The destination's rules still run. See REPOST. On the testnet, the source commit is one that has sequenced. Contract Hub is the same copy between two people.

Next: Commit, then show.

The idea​

The idea